Display sheet holders has been used for over 100 years as noted by U.S. Pat. No. 316,771 to Gerdom, U.S. Pat. No. 379,375 to Delano, U.S. Pat. No. 557,932 to Yarnall, and U.S. Pat. No. 600,852 to Baisley.
The early patent of Gerdom U.S. Pat. No. 316,771 used brass or spring metal for his sleeve to permit insertion of the web or sheet material. A bar holding the sheet material was slipped into the sleeve which was sprung outwardly to receive the bar and web material with the bar positioned so as to prevent the web from being pulled from the sleeve. Web gripping devices forming a part of the bar or sleeve are shown by Baisley and Yarnall for example.
More recent patents such as Pfleghardt U.S. Pat. No. 867,750, Johnson U.S. Pat. No. 2,350,236, Olson U.S. Pat. No. 4,393,915 and U.S. Pat. No. 4,525,946 and Pynenburg U.S. Pat. No. 5,927,671 show other web type holding and securing devices.
Hahn U.S. Pat. No. 6,474,009 is typical of a clip mechanism for securing the web in a holder as is also Skypala U.S. Pat. No. 6,170,182, Greenwell U.S. Pat. No. 3,388,493, Marie U.S. Pat. No. 2,512,447 and Lee U.S. Pat. No. 719,597.
Baisley mentioned above provides a stop for limiting the depth of insertion of the web or sheet material.